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PULLEY CREATOR

── K-Section Poly-V Idler Generator ──
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░▒▓ ABOUT THIS TOOL ▓▒░
Generates a parametric K-section poly-V idler pulley for 3D printing. Select a vehicle preset or dial in your own dimensions. Download a print-ready .STL directly, or grab the .scad source for OpenSCAD. Print in PA12 Nylon or ASA.
VEHICLE PRESET

⚠ Preset OD values are estimates (±2–3mm). Verify with calipers before printing.

BEARING PRESET
PULLEY GEOMETRY
6 ribs

K6 (6-rib) is standard XJ serpentine. 4–12 supported.

70mm

Rib tip outer diameter. 65–80mm typical for XJ idler.

3.5mm

Belt retention lip rise above rib tips. 0 = no flanges.

2.5mm

Axial width of each side flange.

BEARING & BOLT
40mm
17mm
12mm
0.3mm

0.30 = PA12 tight press. 0.25 = ASA. 0.20 = light + CA glue.

18.5mm

Through-bore for mounting bolt. M16=18.5, M12=14.5, M10=11.5

CROSS-SECTION PREVIEWlive · not to scale
26.4mm77.0BRG POCKET

Bearing pocket shown at top. Closed shoulder at bottom — print face down.

COMPUTED DIMENSIONS
Rib contact OD70 mm
Flange OD77.0 mm
Total face width26.36 mm
Belt contact zone21.36 mm (6 × 3.56mm)
Bearing pocket⌀39.70 mm × 12mm deep
Closed shoulder14.36 mm
Bolt through-bore⌀18.5 mm
Retainer cap OD⌀39.30 mm
PRINT & ASSEMBLY NOTES

Orientation: Closed shoulder face DOWN. No supports needed.

Walls: 4+ perimeters. 45%+ gyroid infill. 0.20mm layers.

Material: PA12 Nylon (preferred) or ASA. Dry filament mandatory.

Bearing: Press with socket + soft hammer. Never strike outer race.

Bolt: Clamp INNER RACE only. Snug + 1/4 turn. Do not overtorque.

Two parts: Pulley body + retainer cap. Press cap after bearing install.

EXPORT

STL — Print-Ready

STL generated in-browser using 128-segment geometry. May take 5–15 seconds.

OpenSCAD — Fully Parametric

Open in OpenSCAD → F6 to render → Export STL